Refrigerating apparatus



July 17, 1962 J. WEIBEL, JR., ETAI.

REFRIGERATING APPARATUS 5 Sheets-Sheet 1 Filed NOV. 21, 1958 INVENTORS Jo/m Weibel, Jr. BY Raymond Al. Manley Their Afforney y 1962 J. WEIBEL, JR., ETA]. 3,044,682

REFRIGERATING APPARATUS Filed Nov. 21, 1958 3 Sheets-Sheet 2 INVENTOR.S

M John We/bel, Jn

Raymond N. Man/ey Fig. 4 mg,

Their Af/arney ly 17, 1 6 J. WEIBEL, JR., ETAI. 3,044,682

REFRIGERATING APPARATUS Filed Nov. 21, 1958 3 Sheets-Sheet 3 INVENTOR.8 Ja/m Weibel, Jr.

Raymond IV. Manfey BY 2 g7 Their Affo may United States Patent Ofiice Patented July 17, 1962 3,044,682 REFRIGERATIN G APPARATUS John Weibel, Jr., and Raymond N. Mantey, Dayton,

Ohio, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed Nov. 21, 1958, Ser. No. 775,640 4 Claims. (Cl. 23058) 50 and 52 respectively formed in the main frame 20. To

\ conserve on space, the cylinder bores 50 and 52 are both arranged in the same plane and are directly opposed to one another. Each of the connecting rods is provided with a relatively narrow ring-like portion 55 which en- I circles the eccentric 40 and is provided with a relatively pics a minimum amount of space and which operates with a minimum amount of noise and vibration- It is another object of this invention to provide a small sealed multiple cylinder motor-compressor unit which lends itself to-mass production at a low cost.

It is another object of this invention to provide a motorcompressor unit having a simplified and improved arrangement for suspending the. moving parts within the motor-compressor casing.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a vertical sectional view taken substantially on line 11 of FIGURE 2;

FIGURE 2 is a plan view with parts broken away;

FIGURE 3 is a side elevational view with parts broken away showing the motor-compressor mechanism disposed within its housing;

FIGURE 4 is a bottom view of the motor-compressor assembly; and

FIGURE 5 is a fragmentary sectional view taken substantially on line 55' of FIGURE 1.

Referring now to the drawing wherein a preferred embodiment of the invention has been shown, reference numeral 10 generally designates "a sealed housing which serves to enclose the motor-compressor mechanism. This housing 10 consists of a pair of drawn sheet metal shell elements 12 and 14 which are welded together at their line of juncture 16 so as to form a hermetically sealed casing into which the refrigerant to be compressed is supplied through the inlet fitting 18.

The motor-compressor mechanism includes a main frame or casting element 20 which is provided with an upper bearing 22 and a lower bearing 24 within which the main drive shaft 26 is journaled. A motor rotor 28 is secured to the upper end of the shaft 26 as best shown in FIGURE 1 of the drawing. A motor stator 30 is fixed to the upper portion of the main frame 20. The stator 30 is preferably Welded in place on the frame 20 as indicated at 32. The motor is of the two-pole type so as to provide high speed operation of the compressor. In this manner a compressor of a given output rating may be made much smaller than if a lower speed four-pole motor were used.

As best shown in FIGURE 1 of the drawing the frame 20 is provided with an end thrust bearing ledge 34' which serves to limit the downward movement of the main drive shaft 26. A hardened steel washer 36 is placed on the relatively soft steel bearing ledge 34 so as to protect the ledge 34 from excessive wear. An eccentric portion 40 is provided on the shaft as shown and cooperates with a pair of connecting rods 42 and 44 which drive the pistons 46- and 48 respectively operating within cylinder bores wide bearing surface at the point where the connecting rod pushes against the eccentric during the compression stroke. Each of the cranks is provided with an oflfset portion which further makes it possible to arrange the cylinders in alignment with one another.

For purposes of illustration, special bearing inserts 57 and 59 have been provided between the bearing surfaces on the shaft and the bearing surfaces on the frame which supports the shaft. A counterweight 53 is secured to the bottom side of the eccentric portion 40 by means of one or more cap screws 54. The enlarged bearing portion on the shaft 26. has one or more apertures 56 extending therethroug-h on the same side of the shaft from which the eccentric portion 40 projects so as to better balance the rotating parts of the compressor. By virtue of-providing an enlarged bearing pontion on the shaft 26 in this manner it is possible to utilize this enlarged portion to counter-balance the eccentric portion 40 while at the same time improving the bearing characteristics of the motor.

The lower end of the shaft 26 has secured thereto an end thrust plate 60 which is larger in circumference than the lower end of the shaft 26 with the result that it extends out over the bottom circular bearing projection 62 formed on the frame 20. This plate then serves to limit the upward movement of the shaft during shipment and also during operation of the compressor.

The frame 20 is adapted to be supported on a helical spring element 64 which has its lower end resting on the bottom wall of the casing 10 as best shown in FIGURE 3. A positioning spring locating member 66 which is welded or otherwise secured to the bottom wall of the casing 10 serves to hold the helical spring 64 against sidewise movement but does not in any way restrict rotation of the helical spring 64, A stamped sheet metal guard member 70 is disposed adjacent the lower end of the main drive shaft as shown in FIGURE 3 and this member is provided with a central lubricant receiving aperture 72 which communicates with a central aperture 74 provided in the main drive shaft 26. The bottom portion of the casing 10 is adapted to contain a supply of lubricant which I completely surrounds the helical spring 64 and the bottom of the frame 20. Radially projecting oil passages 76 and 78 are provided as shown in FIGURE 3 and cooperate with the central apertures 74 of the drive shaft to centrifugally feed oil to the lower bearing surfaces and also feed oil upwardly through oil passages 80 and 82 formed in the shaft. The oil passage 82 serves to feed oil upwardly until it reaches a radially projecting oil passage 84 which supplies lubricant to the eccentric portion of the shaft. The oil passage 80 extends upwardly until it corn= municates with the radial oil passage 86 which feeds oil to the upper shaft bearing.

U-pon starting and stopping the operation of the motor rotor there is a tendency for the compressor stator and the frame 20 to rotate and in order to counteract this torque, the frame 20 is provided with outwardly extending projecting ears orlugs 90 which abut against coil spring elements 92 which in turn abut against fixed brackets or lugs 94 welded or otherwise secured to the side walls of the casing 10 as best shown in FIGURE 2. The top wall of the casing 10 has secured thereto a sheet metal stamping 95 which telescopes over the upper end of the main drive shaft 26 in spaced relationship to the shaft 26 so as to restrict excessive sidewise movement of the upper end of the shaft 26 during shipment and handling. During normal operation of the compressor the shaft would not engage the member 95.

The gas to be compressed flows from the interior of the casing downwardly through the standpipes 96 which lead to the inlet muffler chamber 98 from whence the refrigerant flows through passages 100 which lead into the usual suction chambers 102 formed in the cylinder heads 104. From the chambers 102 the gas flows into the compression chambers by the usual suction ports 108. Reed valves 110 allow the gas to enter the suction chamber and prevent the reverse flow of gas, The compressed gas leaves the compression chamber through outlet ports 105 which in turn are controlled by reed valves 112 in accordance with usual practices. The compressed gas then enters the outlet chambers 114 formed in the cylinder head and from there the gas flows through passages 116 formed in the casting into muffler chambers 118 also formed in the frame casting 20. The compressed gas leaves the muffler chambers 118 through the usual discharge lines 120 which convey the compressed gas into a common discharge manifold 122 which leads exteriorly of the casing 10.

While the form of embodiment of the invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, a may come within the scope of the claims which follow.

What is claimed is as follows:

1. In a motor-compressor unit, a casing, a motorcompressor supporting frame disposed within said casing, a helical spring disposed between the bottom of said frame and the bottom wall of said casing for supporting said frame, torque snubbing spring means disposed between portions of said frame and the side walls of said casing, said frame having a pair of vertically aligned bearing apertures formed therein, a main drive shaft journalled in said bearing apertures, a motor rotor secured to one portion of said shaft, a motor stator carried by said frame and surrounding said motor rotor, said shaft having an eccentric portion disposed between said bearing apertures, the radius of one of said bearing apertures being at least as great as the maximum radius of said eccentric portion whereby said eccentric portion may be passed through said one bearing aperture, said frame having formed therein a pair of aligned compression chambers on opposite sides of said shaft, pistons in said chamers, and connecting rods drivingly connecting said pistons to the eccentric portion of said shaft, each of said connecting rods being offset intermediate its ends whereby each of said connecting rods engages a different portion of said eccentric.

2. In a motor-compressor unit, a main frame having a pair of vertically aligned bearing apertures formed therein, a drive shaft journalled in said bearing apertures, motor means for rotating said shaft, said drive shaft including an enlarged central bearing portion journalled in one of said bearing apertures and a relatively smaller bearing portion journalled in the other of said bearing apertures, said shaft having an eccentric portion disposed between said bearing portions and having a maximum radius less than the radius of said enlarged central bearing portion,

compressor means drivingly connected to said eccentric portion, said frame having an integrally formed flange subtending a portion of said central bearing portion and arranged to limit the downward movement of said shaft, and means secured to the bottom end of said shaft for limiting the upward movement of said shaft.

3. In a motorcompressor unit, a main frame having a pair of aligned bearing apertures formed therein, a vertically disposed drive shaft journalled in said bearing apertures, said drive shaft including a first relatively large bearing portion intermediate its ends journalled in one of said bearing apertures and a second relatively small bearing portion journalled in the other of said bearing apertures, said shaft having an eccentric portion disposed between said bearing portions, said enlarged bearing portion including axially extending aperture means formed therein for reducing the weight of said shaft on the side of the shaft on which said eccentric portion projects, said frame having an integrally formed flange arranged adjacent the lower end of said relatively large bearing portion to limit the downward movement of said shaft, and means secured to the lower end of said shaft for engaging the bottom of said frame for limiting the upward movement of said shaft.

4. In a motor-compressor unit, a casing, a main frame disposed within said casing and having a pair of aligned bearing apertures formed therein, a vertically disposed drive shaft journalled in said bearing apertures, said drive shaft including an enlarged central bearing portion journalled in one of said bearing apertures and a relatively smaller bearing portion journalled in the other of said bearing apertures, said shaft having an eccentric portion disposed between said bearing portions, said frame having an integrally formed end thrust bearing arranged to limit the movement of said shaft in the one direction, and means secured to one end of said shaft for limiting the movement of said shaft in the other direction, said enlarged bearing portion including an axially extending aperture formed therein for reducing the weight of said shaft on the side of the shaft on which said eccentric portion projects, said frame having a downwardly extending circular projection surrounding the lower end of said shaft, a helical spring loosely engaging the outer portion of said downwardly extending projection, said casing having a pocket formed on its bottom wall for receiving the lower end of said helical spring.

References Cited in the file of this patent UNITED STATES PATENTS 2,020,987 Ayres Nov. 12, 1935 2,246,868 Trask June 24, 1941 2,423,719 Muffly July 8, 1947 2,463,035 Heitchue Mar. 1, 1949 2,622,788 Ramclow Dec. 23, 1952 2,801,045 Philipp July 30, 1957 2,853,226 Maniscalco Sept. 23, 1958 2,855,139 Weibel Oct. 7, 1958 FOREIGN PATENTS 268,342 Great Britain Aug. 4, 1927 914,499 Germany July 5, 1954 

